Special chemical dispensers are employed for institutional washing apparatuses such as ware-washing machines. Automatic detergent dispensers utilize detergent in special packaging. There are several goals that must be achieved in packaging such detergent. The first is the effective, safe distribution of the detergent. In association with the effective distribution of the detergent, the dispensing rate of the detergent must be uniform. Solid detergents, i.e., powders, tablets, granules and bricks, are generally preferred since they are more concentrated and reduce the overall size of the container. The package must permit all of the detergent to be dispensed.
Further, the overall cost of the container and the process of packaging the detergent in the container is very significant. The cost of the detergent will generally include the detergent composition itself, the detergent container, and any processing required to package the detergent and subsequently use the detergent. Thus, the container should be designed in a way to reduce these costs, as well as the cost of the dispenser. Generally, these are single-use containers which are discarded after use.
A further goal is simplification. The detergent container and dispensing system should be as simple to use as possible. Further, it is desirable to make the overall packaging system as simple and inexpensive as possible without affecting safety.
There are many different containers currently designed for solid commercial detergents. These can range from rigid plastic pans which hold solid bricks of detergent to flexible plastic bags which hold powdered detergent or pelleted detergent. One such container is disclosed in pending application Ser. No. 08/749,834, filed Nov. 15, 1996. This system employs a container which holds detergent. Water is sprayed on the detergent dissolving it. The dissolved detergent is then fed to the washing apparatus. This application discloses a flexible-walled container which has a rigid injection-molded plastic screen. This is a relatively simple container. However, it has some limitations. Because it is formed from a flexible-walled material, i.e., a plastic film, it is difficult to fill. It is also not compatible with powdered detergent. Further, the plastic film must be formed into a bag and adhered to the rigid plastic screen. This, again, increases costs. Due to the shape of the plastic bag that is attached to the plastic screen, the quantity of detergent which can be held by such a container is reduced. This also requires a special insert to align the container in the dispensing unit.
Other rigid containers are disclosed in, for example, Bird U.S. Pat. No. 5,147,615 and Young U.S. Pat. No. 5,007,559. These are filled through an opening, and then the opening is capped with a screen. This makes filling difficult. Also, these containers generally have shoulders which can interfere with complete dissolution of all detergent within the container.